1. Field of the Invention
The present invention relates to an active headrest assembly for a vehicle which has a lumbar unit cooperating with an active plate.
2. Description of the Prior Art
As is well known in the art, an active headrest assembly for a vehicle serves as a device in which a headrest cooperates with an active plate installed in a seat back to help protect an occupant's head and neck against neck injury.
A conventional active headrest assembly includes an active plate, which is transversely arranged in the seat back frame of a seat back, and a headrest, which is connected to the active plate to rotate around the upper end of the seat back frame. If shock is generated when the vehicle is in a collision, rearward force is applied to the active plate by an occupant leaning on the seat back. As the active plate is rotated rearward by the application of the force, the headrest is rotated forward. By this fact, the headrest comes into close contact with the rear portion of the occupant's head and prevents the occupant's neck from being injured.
However, in order to ensure the reliable functioning of the headrest, the active plate must project forward to some extent. The projecting active plate may decrease the riding comfort of an occupant who leans with his or her back on the seat back.
The information disclosed in this Background of the Invention section is only for enhancement of understanding of the background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art that is already known to a person skilled in the art.